1. Field of the Invention
This invention concerns a device for use by a health care technician for collecting blood specimens from patients, and more particularly relates to a multi-sample blood collection needle device which minimizes the possibility of needle-stick accidents after use.
2. Description of the Prior Art
Devices for withdrawing blood specimens from patients and causing said blood to directly enter a sealed storage vial have been in use for many years. Such devices have, for example, been marketed under the trademark Vacutainer by the Becton-Dickinson Company of New Jersey, and under the trademark Venoject by the Kimbell-Ternmo Company of California. These blood-collecting devices are generally comprised of a hollow needle sharpened at a forward, patient application extremity and at a rearward extremity, and a connector hub mounted upon the needle. The connector hub is adapted to threadably engage the front extremity of a circular cylindrical adapter having an open back extremity. The needle is thereby positioned upon the center axis of the adapter, disposing the rearward extremity of the needle about one third of the distance proceeding into the cylinder toward said open back extremity.
In use, an elongated circular cylindrical collection tube is employed, having a closed bottom extremity and opposed mouth extremity sealed with a rubber stopper. The collection tube contains a vacuum and has an outside diameter which permits close-fitting insertion into said adapter. When the forward extremity of the needle has entered the patent's vein, the collection tube is pressed forwardly, causing the rearward extremity of the needle to pierce the rubber stopper. The evacuated condition of the tube causes blood to flow into the tube. The tube containing the blood specimen is then removed, whereupon the resilient characteristics of the rubber stopper automatically re-seal the mouth extremity of the collection tube. By virtue of such construction and use, the barrel member merely serves to align the needle with the collection tube, and does not come into contact with the blood. Accordingly, the same barrel member may be employed repeatedly.
Contamination by accidental needle sticks has generated a plethora of inventions in the syringe field, particularly with the increased risk of exposure of medical personnel to AIDS contaminated needles. Some of the "safety" syringes designed to reduce risk of accidental sticks are seen in U.S. Pat. Nos. 5,167,641; 5,180,370; 5,190,526 and 5,211,628. In general, such devices employ coil springs which retract the needle into the tubular housing of the syringe.
It is to be noted that, although syringes are somewhat related in design to Vacutainer-type blood collecting devices, there are significant differences, especially in the design of the needle and manner of function of the devices. Syringes are designed primarily for injecting substances into a patient. If used to remove a blood specimen, as was the practice long ago, the specimen would have to be transferred to a separate collection container, and the barrel and plunger of the syringe would then either be discarded or sterilized prior to re-use.
The current manner of use of Vacutainer-type devices is such that, once the blood specimen has been collected, the needle is withdrawn from the patient's vein and is placed point first in a sharps container. The needle is then unscrewed from the adapter and deposited into the container, and the adapter is set aside for re-use. The problem with such manner of use is that, after withdrawing the needle from the patient, there is a period of time during which the needle point is exposed. It is during this time period that inadvertent needle sticks occur.
The recent prior art includes a safety-modified Vacutainer wherein a plastic sleeve/shroud is slipped down over the needle after it is withdrawn, and is then locked into place onto the adapter. However, there is still the risk interval from the instant of removal of the needle from the patient to its securement by the shroud. In addition, the entire apparatus, including the adapter, is discarded, which represents increased costs.
It is accordingly an object of the present invention to provide a Vacutainer-type blood-collecting device which poses less risk to health-care personnel employing the device.
It is another object of this invention to provide a device as in the foregoing object which provides for substantially automatic retraction of the needle to a secured disposition.
It is a further object of the invention to provide a device of the aforesaid nature which permits re-use of the adapter component.
It is a still further object of this invention to provide a device of the aforesaid nature which is easy to use and of simple construction amenable to low cost manufacture.
These and other beneficial objects and advantages will be apparent from the following description.